Thursday, 29 June 2017

Fixing Rx_Core with SERDES primitive for Xilinx 7 Series FPGAs

I have been having trouble in implementing a Serializer and Deserialize (SERDES) primitive with my VHDL Rx_Core Firware for the past few days, which was resolved today. Aparantly for the new Kintex and Virtex 7 series FPGAs they have updated their primitives to handle more incoming data. Earlier mine was a 4 bit, I had to replace it with a new one of 8-bits, thus, grounding the higher order bits.
more info on the same can be found in the application note by Xilinx: LVDS Source Synchronous 7:1 Serialization and Deserialization Using Clock Multiplication

Xilinx Primitives are components that can be implemented in our HDL. They are defined in the UNISIM library.

Next challenge that appears in the vicinity is fixing the clock multiplication problem to run our Rx_Core. Timon had just now suggested me to look into PLLs to achieve this. I also have help from Daniel from University of Valencia, Spain who is working on the gigabit transceiver (GBT) framework for optical communication. So, we can get going now!

Saturday, 3 June 2017

A day of firsts.. an account of my first visit to a foreign country

I could not think of a more apt title as this day, 2nd June 2017 is one of the biggest days of my life (like literally the biggest, due to time difference, you see).

Today morning, 4:45am I am about to set sail (not literally) to a foreign land. It is going to be Genève, Suisse! The first ever visit to a foreign country. Though it sounds like an amazing idea where you can't stop yourself to overjoy with happiness, but for me, it had mixed feelings. The place no doubt would be amazing but my concern was the life there, the cultural difference and most importantly the work for which I am taking this journey. It would be my first paid work, that I can officially call, 'a job'.

I reached the Indira Gandhi International Airport Terminal 3 quite early, 2 AM in New Delhi. I was aware of the proceedings later so I bid farewell to Mom and Dad outside and went in. Though, Mom and Dad stayed there until the flight left. Love you guys, you're the best! I went in to see my flight EY-211 Etihad Airways (This was a Boeing 777-300) and went directly to their counter to check in. I left my check in luggage there and proceeded. I received my boarding pass, a luggage slip and an immigration form. Filled it up and moved to the next step: the immigration counter. These guys 'tried' to look very strict but it was interesting as I was quite in a mood of confidence. (lol) So, after getting a stamp there I moved to the security check where I left my coat and belongings in a tray to be checked and after that proceeded to the waiting area. This place was marked by shops and showrooms of brands from all over the world. The first one being the Vine Shop. Elegant vines from all over the world costing in Lakhs! If felt funny in the stomach here but I moved ahead. Gate No 7 was my flight waiting but I still had a little over 1 hour so I went to eat something instead and on the way purchased a travel adapter for Europe. This was necessary. At 4:00AM, when they opened the gates for boarding, I went in. It was an interesting process and now I was in the flight, for the first time waiting anxiously for it to lift off.

The flight experience was amazing, the take off and landing specially. There is nothing much to do after the flight is in the air. So I won't write much about it. Next I reached Abu Dhabi Airport T3 at 7AM in the morning (Abu Dhabi local time). The connecting flight was at 9:00AM (Abu Dhabi local time). We got off the place, moved to the security check and done. Here I accidently lost my luggage slip (though it was not a necessary thing) and I had to go back and look when I realized it. More importantly, all this while you will be in a state of panic regarding your passport. Keep it safe as you don't want yourself left with the Arabs and their security personnel. I then went to gate number 53 from there passing through all the showrooms as were at IGI T3. There I had to wait for sometime before the gates open. Here, because it is worth mentioning, I saw, one of the most beautiful persons I've ever seen, like literally, she was out of the world! and she sat right in front of me! But she had to take another flight and it was just a brief encounter.

Sunrise (just after take off from India)
Landing at Abu Dhabi (Look! Desert Below)

When the gates opened, our boarding pass was checked and we went in the bus that took us to our plane EY-51 Etihad Airways. This was an Airbus A330-300 and a little smaller compared to my previous plane. Many Indians accompaied me till Abu Dhabi but later on, there were mostly Europeans and a few other nationals from Japan, Thailand and England. I fell asleep soon in this and missed the take off. It was a long flight ~8hours and I woke up a couple of times to have lunch or to wash my face or to watch the TV. We flew at 40,000 ft so it was too sunny to keep the window shutter open. It was all closed and again, nothing much to do. I used to turn on the Plane's Nadir camera at certain places, like when we flew over Venice, over the Adriatic Sea and also when we flew over the Alps (It was -66 degree C at that point outside!). And finally when it was 35 mins to reach Geneva, our captain announced, we were about to decent and we should put our seat belts on. I adhered. It was all amazing and when we flew over Geneva, I could say nothing else, but it was heaven!

Buses! (a type of)
Geneva Airport!

I landed at the Geneva Airport at around 2:50PM (Geneva Local Time). The Airport was a comparatively small one and the person sitting next to me (whose this Geneva visit was the 17th) told me that they shut down the airport at night so that people living nearby do not get disturbed. He was a Sri Lankan Diplomat and was there for a UN visit. We arrived here and proceeded to the arrivals counter where I got my passport stamped and directly went for the luggage collection counter number 5. The bag that I left in Delhi was here! I took my belongings and also on the way collected a free travel ticket for 1 day in Geneva. This was valid in all buses for 80mins to go around in Geneva. The weather outside was very pleasant, sunny and cool at the same time.

Outside the airport, I helped out an African fellow visitor in finding the correct direction to his bus stop but ironically myself boarded the wrong bus! Unaware of the destinations, I accidently boarded the wrong bus 'Y' Destination to Ferney-Voltaire and ended up reaching France! The same bus at the destination, changed its route to Destination Val-Thoiry (in France) and it dropped me at the CERN entrance without much hassle. (Half of CERN is in Suisse and other half in France!) It look me around 45 mins in the Bus to reach when it could be done in less than 20mins.

Next I went to the CERN main reception, Building 33. It is a relatively small office. They directed me to the Hostel from inside as I did not yet have an access card. As it happens, I was the first summer student to arrive and the receptionist at the hostel building number 39 greeted me. I had to show her my invite, my room bookings and passport and then she handed me over my hostel card. All rooms and buildings access is RFID based. So, you can't really get into rooms without an access card. I had reached at around 4pm and it was a Friday. I knew if I didn't get access to the internet today, I will have to wait till Tuesday. If not done, I would not be able to even contact home and tell that I reached safely. It was a major issue. I immediately went back to the reception to inquire this and she directed me to building number 55. This is situated at the entrance B, a little over 10mins of walk from the Hostel. There, on the 2nd floor, they had the computer service desk. She asked me if I already had a CERN account. Unaware about it, I told I did not but I'm not sure. She checked and Voila! There was an account! Thank you summer student team! She was very supportive and helped me all the way to activate my CERN computer access, set up the Wi-Fi access for my devices and set up the email ID. ( Just a little shy of the closing time, I got got access to WiFi! First things first, I called up home!

Room, again!

Restaurant 1 (Not the building!)

Nataraj @ CERN
Route Marie CURIE (The buildings are no 39 and 38, L to R)

Honestly, the time after this was boring! I knew no one and it all came as a cultural shock. Added to it, Building 38 (where I got room number 29, bed A) is a Co-Ed hostel. Yes, it is. Though this usually happens to girls, I instead, felt a little insecure. (though, this feeling passed the next day, just saying) I passed by Restaurant 1 here (the main hangout place) where everyone (scientists, students, PhD fellows and even Nobel laureates) come together in the evening, hangout, eat and share a beer! Uncertain of the protocols, I simply went in. I wore a tracksuit upper and Jeans and floaters (or slippers, as we call them in India). I took some time to understand whats going on in this place. There was food all around and yes, it was a Buffet! So, step 1, find the plates. Get the gear (cutlery) and you are ready to explore. As tempting as it was to see the huge collection of beer, I kept my hands off those babies for today! I had a decent dinner (believe it or not, it was almost 8:30 and it was bright out there as day!). It costed me 12.50 CHF (1 Suisse Francs (CHF) = 68.45 INR).

The cuisine at Restaurant 1
Looking out of the beautiful scene from my room's window, I decided to call it a day. And went off to sleep. A beautiful day worth recording! Thank you God!
Peace Out! :)